Particle image velocimetry measurement of flow fields in a mixed-flow pump with non-uniform tip clearance

Abstract In order to better understand the flow characteristics of mixed-flow pump with non-uniform tip clearance, a test rig is established and the flow fields of various cross section in impeller are studied based on particle image velocimetry technology. The velocity vector distributions of three cross sections, e.g., impeller blade inlet, middle and outlet, were measured. The influences of flow rate and eccentricity on the flow fields of mixed-flow pump with non-uniform tip clearance were analyzed, and the relative velocity distribution of different positions at the same cross section is quantitatively discussed. The results show that the external characteristics have been greatly affected by the eccentricity of impeller. There is a significant negative correlation between eccentricity and efficiency. The maximum head and efficiency drop of eccentric impeller reach 11% and 20% separately. With the increase in eccentricity, the secondary flow phenomenon increases, such as backflow and vortex flow in impeller flow passage. Vortex structure is easily formed in the end wall region, which will give rise to backflow and even blocks the flow passage near impeller hub. The energy loss increases continuously in this process which is the main reason for the significant drop in efficiency. The research results are instructive for revealing the flow characteristics of flow fields of mixed-flow pump with non-uniform tip clearance. Graphic abstract

[1]  Lingjiu Zhou,et al.  Vibration of Shaft System in the Mixed-Flow Pump Induced by the Rotor-Stator Interaction under Partial Load Conditions , 2018, Shock and Vibration.

[2]  H. Horiguchi,et al.  The Effect of Casing Geometry on Rotordynamic Fluid Forces on a Closed Type Centrifugal Impeller in Whirling Motion , 2011 .

[3]  Dazhi Pan,et al.  Numerical and Experimental Investigation of Tip Leakage Vortex Cavitation Patterns and Mechanisms in an Axial Flow Pump , 2015 .

[4]  Ronald D. Flack,et al.  Laser Velocimeter Measurements in a Centrifugal Flow Pump , 1989 .

[5]  Chen Qi,et al.  Research on Fractal Model of Tangential Contact Stiffness between Cylindrical Surfaces Considering Friction Factors , 2016 .

[6]  Ning Zhang,et al.  Unsteady flow structure and its evolution in a low specific speed centrifugal pump measured by PIV , 2018, Experimental Thermal and Fluid Science.

[7]  Huijing Yuan,et al.  PIV measurement on internal instantaneous flows of a centrifugal pump , 2011 .

[8]  W. Shi,et al.  Particle image velocimetry experiment of the inlet flow field in a mixed-flow pump during the startup period , 2020, Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy.

[9]  Christian Brix Jacobsen,et al.  Flow in a Centrifugal Pump Impeller at Design and Off-Design Conditions—Part I: Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) Measurements , 2003 .

[10]  Jianjun Feng,et al.  Time-Resolved Particle Image Velocimetry (PIV) Measurements in a Radial Diffuser Pump , 2009 .

[11]  Xie Zhifeng,et al.  Influence of T-shape tip clearance on performance of a mixed-flow pump , 2018 .

[12]  R. A. Van den Braembussche,et al.  Experimental investigation of the flow in the vaneless diffuser of a centrifugal pump by particle image displacement velocimetry , 1989 .

[13]  Ning Zhang,et al.  Effects of modifying the blade trailing edge profile on unsteady pressure pulsations and flow structures in a centrifugal pump , 2019, International Journal of Heat and Fluid Flow.

[14]  L. Tan,et al.  Symmetrical and unsymmetrical tip clearances on cavitation performance and radial force of a mixed flow pump as turbine at pump mode , 2018, Renewable Energy.

[15]  Lingjiu Zhou,et al.  Mechanism and propagation characteristics of rotating stall in a mixed-flow pump , 2020 .

[16]  Pan Tang,et al.  Effect of manifold layout and fertilizer solution concentration on fertilization and flushing times and uniformity of drip irrigation systems , 2018 .

[17]  Tan Lei,et al.  Role of blade rotational angle on energy performance and pressure fluctuation of a mixed-flow pump , 2017 .

[18]  L. Belyakova,et al.  Kinetics of chemisorption of trimethylisothiocyanatosilane and trimethylisocyanatosilane on silica and properties of the surface compounds , 1989 .

[19]  Hong Li,et al.  INFLUENCE OF A FIXED WATER DISPERSION DEVICE ON JET DISPERSION AND RANGE FROM AN IMPACT SPRINKLER , 2019, Irrigation and Drainage.

[20]  Li Wei,et al.  Numerical Calculation of Internal Flow Field in Mixed-flow Pump with Non-uniform Tip Clearance , 2016 .

[21]  Yabin Liu,et al.  Tip clearance on pressure fluctuation intensity and vortex characteristic of a mixed flow pump as turbine at pump mode , 2018, Renewable Energy.

[22]  W. Shi,et al.  Effect of a Nonuniform Radial/Axial Tip Clearance on the Flow Field in a Mixed-Flow Pump , 2018, Strength of Materials.

[23]  R. Agarwal,et al.  Diagnosis of internal energy characteristics of mixed-flow pump within stall region based on entropy production analysis model , 2020 .

[24]  Bin Chen,et al.  Experimental study of flow field in interference area between impeller and guide vane of axial flow pump , 2014 .

[25]  Hong Li,et al.  COMPARISON OF ROTATION AND WATER DISTRIBUTION UNIFORMITY USING DISPERSION DEVICES FOR IMPACT AND ROTARY SPRINKLERS , 2019, Irrigation and Drainage.

[26]  R. Agarwal,et al.  Process simulation of Chemical Looping Combustion using ASPEN plus for a mixture of biomass and coal with various oxygen carriers , 2020 .

[27]  Jinjia Wei,et al.  A novel experimental facility for measuring internal flow of Solid-liquid two-phase flow in a centrifugal pump by PIV , 2017 .

[28]  W. Shi,et al.  Influence of tip leakage flow and inlet distortion flow on a mixed-flow pump with different tip clearances within the stall condition , 2020, Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy.

[29]  R. Agarwal,et al.  Expansion of High Efficiency Region of Wind Energy Centrifugal Pump Based on Factorial Experiment Design and Computational Fluid Dynamics , 2020 .

[30]  W. Shi,et al.  Energy characteristics of mixed-flow pump under different tip clearances based on entropy production analysis , 2020 .

[31]  Weiyang Fei,et al.  CFD simulation and PIV measurement of liquid–liquid two-phase flow in pump-mix mixer , 2016 .

[32]  Li Wei,et al.  Experimental Study on Orbit of Shaft Centerline of Mixed-flow Pump during Starting Period , 2016 .

[33]  Ling Zhou,et al.  CFD investigation and PIV validation of flow field in a compact return diffuser under strong part-load conditions , 2015 .

[34]  Yabin Liu,et al.  Spatial–Temporal Evolution of Tip Leakage Vortex in a Mixed-Flow Pump With Tip Clearance , 2019, Journal of Fluids Engineering.

[35]  Leqin Wang,et al.  Dynamic analysis of a planar multi-stage centrifugal pump rotor system based on a novel coupled model , 2018, Journal of Sound and Vibration.

[36]  Lingjiu Zhou,et al.  PIV experiment of the unsteady flow field in mixed-flow pump under part loading condition , 2017 .